By employing a thin silicon sacrificial cap layer for silicide formation we have successfully demonstrated Pd2Si/strained Si1-xGex Schottky-barrier infrared detectors with extended cutoff wavelengths. The sacrificial silicon eliminates the segregation effects and Fermi level pinning which occur if the metal reacts directly with the Si 1-xGexalloy. The Schottky barrier height of the silicide/strained Si1-xGex, detector decreases with increasing Ge fraction, allowing for tuning of the detector's cutoff wavelength. The cutoff wavelength has been extended beyond 8 μm in PtSi/Si0.85Ge015 detectors. We have shown that high quantum efficiency and near-ideal dark current can be obtained from these detectors.
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Electrical and Electronic Engineering